On: Sorry, Lisp. I tried.

[Zak]

Portability between implementations is a bit of a red herring (as you seem to have discovered); most libraries you'd actually want to use run on most implementations you'd actually want to use. Ruby and Python don't give you this either, but they do give you a standard implementation. I suspect a lot of Ruby code you might want to run doesn't work with JRuby or IronRuby.

Portability between operating systems is a more serious problem. I think ECL is the only free implementation that does this well, and most libraries don't seem to be tested on it.

[michaelneale → Zak]

>I suspect a lot of Ruby code you might want to run doesn't work with JRuby or IronRuby.

Not likely. Rails runs fine on jruby at least, and it does every dirty trick under the sun.